Walker and cast reinforcement



Dec. 2, 1969 ML. ARNOLD 3,481,332

WALKER AND CAST REINFORCEMENT Filed Oct. 13, 1965 3 Sheets-Sheet l Dec. 2, 1969 M. L. ARNOLD WALKER AND CAST REINFORCEMENT 3 Sheets-Sheet 2 Filed Oct. 13, 1965 Dec. 2, 1969 ARNOLD WALKER AND CAST REINFORCEMENT 3 Sheets-Sheet 3 Filed Oct. 13, 1965 United States Patent 3,481,332 WALKER AND CAST REINFORCEMENT Marcia Lee Arnold, Salt Lake City, Utah (395 Waterford, Florissant, Mo. 63033) Filed Oct. 13, 1965, Ser. No. 495,437 Int. Cl. A43b 3/04, 13/20 US. Cl. 128-835 14 Claims ABSTRACT OF THE DISCLOSURE A walker for a plaster cast or leg brace with means to permit a ground engaging cleat to rotate 90 or less with respect to the foots longitudinal axis and to return the ground engaging cleat to center when the patients weight is removed. The ground engaging cleat is formed 7 with aninverted U-shape open at the sides. The walker may include a reinforcement for the cast behind the patientsankle.

This invention relates to apparatus for supporting an injured leg or foot and to permit improved ambulation while the leg or foot is incased in a cast and/or brace, and a means of reinforcing the cast.

' "To permit ambulation as soon as possible after setting the injured limb, the leg and/or foot are incased in a cast merit of the walker to the cast. In theory such a walker presents many advantages over the walking iron, princi- .;-pally in that it should permit simulation of the normal rocking motion of the ankle in walking without permitting q movement of the' ankle or foot bones. The previous walker must be tall enough to prevent the us-ers toes from contact- 7 transferred to'the injured limb. The convex shape of'the .ing the ground during the normal rocking motion of walking. This type of apparatus requires the injured leg to be placed in a cast that is longer than the normal leg and results in a greater amount of weight than normal being resilient walking surfatceresults in the tendency for prev'iousw'alker s to sliplawa'y' from surface irregularities on the ground such as rocks, or the edge of a curb. Also the convex-shape provides but a small surface contact area ing the probability that the user will slip and fall.

An attempt was made to eliminate the rocking action requirement substituting aroundswiyeling pad ground contact surface. The person using this walkerwould set the swiveling pad upon the ground or floor and pivot r around that'point advancing his other leg ahead without perceptable rocking action on the injured limb. These de- "vices are, however, free to rotate without rotational stops;

and as a consequence, unless the pad is set squarely upon the ground, there is a tendency for the pad to roll about its axis on its edge thus causing the user to fall.

Casts for a fractured foot and/ or leg are often damaged in use and their fabrication and repair requires considerable time. Reinforcements are frequently made by adding extra layers of plaster impregnated gauze along the sole of the foot and up the back of the ankle. The purpose of this reinforcement is to protect the cast bottom whether a walker is used or not, and to protect the back of the cast when the leg is propped up on a stool or other raised surface. This is time consuming for a person building at "any one time through-the rockingmotion, thus increas- "ice.

the cast and not satisfactory from the standpoint of cast durability. Previous walkers which are attached only to the sole of the cast frequently become loose and must be replaced and the cast repaired.

It has heretofore been demonstrated that the limited rotation and return to center mechanism used with a walking cast will improve a patients mobility. Such an apparatus mechanized in a manner different and more complex than those described herein was used publicly in and about Tarrant County, Tex. prior to the year of 1960. The walking surface of this device was convex and the mounting plate was flat and smooth. Difficulty was experienced in keeping this walker attached to the cast.

It is therefore the object of this invention to provide a more satisfactory walker which can be manufactured economically and overcome the aforementioned problems and disadvantages.

Another object is to provide an improved means to permit the walking surface to rotate degrees or less in relation to the mounting plate, to limit the rotation to an optimum angle and return the walking surface to center between steps. This rotation swings the toes out of the plane of the rocking motion and permits the device to be near the same height as a normal shoe Without bumping the toes when in the act of walking with my apparatus.

Another object is to prevent the twisting action which is ever present during walking, from applying excessive torque to the injured limb by including suitable bearings to reduce rotational friction.

Another object of this invention is to provide a Walker with an improved shock absorbing pad and to provide an increased ground or floor contact area with a concave surface to reduce the probability of the user slipping due to surface imperfections as well as during normal use.

Another object of this invention is to provide a prefabricated cast reinforcement which will improve the durability of the cast and reduce the time required to apply the cast.

Another object of this invention is to provide a cast reinforcement which will also serve as a mount for a walker and/or a mount for a bumper or cushion to be attached to the cast behind the ankle to protect the cast from damage when it is propped up and to protect the object upon which the cast is propped from being damaged by the cast.

These and other objects and advantages of this invention and the means of accomplishing these objects will be made apparent by the following specification, descriptions, drawings of some forms which my invention may ta e.

Referring to the drawings in which similar reference numbers refer to like parts:

FIGURE 1 is a side view of my improved walker attached to a cast.

FIGURE 2 is a bottom view thereof indicating limited rotation of the walking surface and return to the initial position.

FIGURE 3 is a sectional view illustrating a method of providing the working mechanism of my improved walker.

FIGURES 4 thru 14 depict some forms which the lliilltd rotation and return to center mechanisms may ta e.

FIGURE 15 shows' how the maximum contact surface resilient walking surface deflects during the act of walking.

FIGURES 16 thru 19 show for-ms which the maximum contact area resilient walking surface may take.

FIGURE 20 shows an installation of the improved walker on a Walking iron or brace.

FIGURE 21 shows the cast reinforcement device which may be integrated with my improved walker, with other walkers, or used without a walker.

In describing the preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended to be limited to the specific terms selected and it is understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.

Referring now to the disclosure of the drawings:

The walker is shown affixed to a cast which incases a foot and ankle with plaster impregnated gauze 1, wrapped around the walker base plate 2, the vetrical axis of rota tion 3, and the resilient walker surface 4, are shown. The walker is preferably made in different lengths and said vertical axis of rotation 3, shall be located in a line common with the median of the tibia 32, which is the load bearing line of the leg. The screw 5, which provides the structure for said vertical axis of rotation 3, is shown within bearing 6. The resilient material mounting block 8, is shown pivoted on the vertical axis 3, and separated from the mounting base 2, by bearing 7. Items 6, 7, and 8 may be incorporated into a single part made of low friction bearing material in the event manufacturing economy justifies such a change. Holes 34, thru the mounting plate 2, may be filled with plaster and plaster impregnated gauze to key the walker to the cast. FIGURE 4 shows a view into the resilient material mounting block 8, with the resilient material 4, removed to illustrate a method of mechanization of the limited rotation and return to center feature utilizing a coil spring 12, to react against spring mount 11, upon the one end and upon the end of spring slot 10, to provide the return to center force. To permit a change of rotation for use on the opposite foot, pin 11, may be relocated in hole 13, and spring 12, moved to slot 9, to permit the user to convert the unit in stock to the proper rotational direction to meet his present need. It can be seen that the angle of rotation from center is controlled by the length of slot 9 or 10, and the compressed length of spring 12.

FIGURE 6 shows a view into the resilient material mounting block '8, to illustrate a method of mechanization utilizing a torsion spring 14, to provide the return to center force. Cavity 15, size determines the angle of rotation limits by contact with pin 16. To convert the rotation to the opposite direction, move pin 16, to hole 17, and invert spring 14. FIGURE 8 shows a view into the resilient material mounting block 8, to illustrate a method of mechanization utilizing a leaf spring 18, to provide the return to center force. Spring 18, reacts between block 8 and pin 20, affixed to the base plate 2. Cavity 19, width determines the angle and direction of rotation.

It is obvious to the viewer that as shown, the walking surface is free to rotate within the desired angular limits in either direction. By changing cavity 19, the direction of rotation can be changed to manufacture parts which rotate to the left or to the right only.

FIGURE 10 is a sectional view similar to FIGURE 3 with the method of providing limited rotation and return to center, a resilient walking surface, and provisions to mount the walker to a cast or walking iron with but three parts. The resilient walking surface 21, is molded with an integral post 26, which provides the torsional force to return the walking surface to center. The post 26, is adhered or otherwise aflixed to the base 2 or 30, to hold the assembly together and to provide an anchor for the torsion producing post 26. The resilient walking surface 21, is adhered to the bearing surface 22, and pins 24. Pins 24, are provided as an optional feature to mate with pockets in the resilient walking surface 21, to supplement the strength of the adherent which attaches the resilient walking surface 21, to the bearing 22. Limit stop pins 23, may be molded integrally or assembled into bearing 22. Said pins 23, limit rotation by contact with the ends of groove 25. When three or more pins 23, are used spaced equally, a centering restraint is applied to the walking surface 21, to resist sideward, forward, or rearward thrust loads.

In the manner previously described, the pins 23, may be located in the base 2 or 30, and the grooves 25, may be located in the bearing 22, without effect to their function. Likewise, the arrangement of the grooves 25 in relation to the pins 23 may limit rotation to the left only, to the right only, or allow rotation in either direction.

FIGURE 12 illustrates an alternate mechanization to FIGURE 8 to provide the rotate and return to center force with a leaf spring. The spring 36, reacts between the mechanical pivot screw 5, and pin 27, affixed to the resilient material mounting block 8, and the pin 28, afiixed to the mounting plate 2 or 30. The width of cavity 29, determines the limits and direction of rotation.

FIGURE 15 illustrates the rocking motion of the resilient walking surface during the action of walking. As the high surface of the back of the resilient walking surface 4, initially contacts the plane of the ground aa', the initial load is distributed over a small area of resilient material. The resiliency is controlled to cause this initial contact area to deflect and allow a maximum of surface area contact between the resilient walking surface 4, and plane aa. As the leg rotates thru vertical, both the higher forward and rear surfaces of the resilient walking surface 4, are deflected under the users full weight to cause a total surface contact. The procedure in the reverse of the initial contact is reversed as the user rocks forward completing the step and plane aa\ rotates thru horizontal to become plane bb.

FIGURES l6 and 17 illustrate a means of providing controlled resiliency for the Walking surface 4, by removing resilient material with a series of grooves 39, to control the load required to present a maximum area walking surface. The nonslip surface provisions are indicated by serrations 35. FIGURE 17 shows a section thru the resilient walking surface 4, illustrating the higher forward and rear surfaces and their relation to the ground contact planes aa and bb.

FIGURES 18 and 19 illustrate a means of providing controlled resiliency for walking surface 4, by means of a very soft or foam elastomeric material 38, within a cored or hollow elastomeric material shell 37, which may provide an improved wear and gripping surface. The very soft or foam material 38, or the hollow elastomeric shell 37, may be used independently of each other and arranged in a manner to provide the controlled resiliency for walking surface 4, if manufacturing economies indicate that this means is more desirable.

FIGURE 20 illustrates the improved walker afiixed to a brace or walking iron 29, in lieu of direct attachment to the cast.

FIGURE 21 illustrates a cast reinforcement 30, which may be used as a mounting base for a walker or serve as a cast reinforcement without attaching a walker. Mechanical features previously described as being within walker base plate 2, to provide limited rotation and return to center mechanization may be included within said cast reinforcement 30, or means to attach base plate 2, to reinforcement 30, may be provided. Reinforcement 30, may be made of metallic or nonmetallic material, preferably in various sizes. Holes 34, shown in FIGURE 2 may be provided in various locations to mechanically key the reinforcement to the plaster impregnated gauze 1, and thus to the cast. In addition to reinforcing the cast, a firmer foundation for building the cast will save the practitioner time in application of said cast. The reinforcing device 30, may also serve as a mount for an elastomeric or plastic bumper 31, which serves to protect the cast from damage, or when the injured leg is propped up, said bumper 31, may protect furniture or other objects upon which the cast is rested.

The use and application of my improved Walker in connection with an injury to which a cast is applied shall be as follows: the injured leg is first encased in cotton, wool or other padding according to the practitioners choice followed by preliminary layers of plaster impregnated bandage. The flat upper surface of the walker mounting plate 2 or 30, is then applied to the sole of the bandage encased foot and positioned in relation to the tibia 32, so that the vertical axis of rotation 3, is in line with the median line of said bone. The plain mounting plate 2, or the cast reinforcing plate 30, is pressed into the wet plaster to mechanically key said plate to the cast by extruding the soft plaster and bandages 1, into holes 34. Additional plaster impregnated bandages 1, are wrapped in the usual spiral manner to complete the cast. Care must be exercised to restrict bandage or plaster accumulation above the level of the bearing surface 33, or in case the cast reinforcement 30 is used and bumpers 31, are to be applied, attachment provisions for this device must be kept clear.

Operation by the wearer of the improved walker will be in the following manner: contact the heel of the walker to the ground in a normal manner of walking and rock forward to apply weight to the Walker. As weight is applied, start to rotate about the vertical axis 3, with the toes traveling in an outward, or away from the body, motion. With little practice, the rocking and rotating action will become one smooth motion. When the rotation limit stop is approached, the rocking motion may proceed forward past vertical without danger of striking the toes upon the ground as weight is transferred to the opposite foot.

It is to be understood that the forms of the invention herewith shown and described are to be taken as the preferred embodiment. Various changes may be made in the shape, size, and arrangement of parts. For example, equivalent elements may be substituted for those illustrated and described herein, parts may be reversed and certain features of the invention may be utilized independently of the use of other features. Mechanisms constructed in accordance with this invention may substitute flexible plastics for elastomeric materials. The return to center mechanism may be performed by flexible nonmetallic or metallic materials. Leaf springs may be of metallic or nonmetallic materials. Bearing materials and the mounting base may be either metallic or nonmetallic.

Having described my invention, I claim:

1. A walker for use on an artificial support for a human leg comprising a first element formed as a base adapted to be anchored to the sole of said support, a second element formed as a ground engaging cleat, means rotatably.

mounting said first and second element to each other with said second element depending from said first element, stop means limiting rotation of said elements relative to each other and means normally urging said elements into a neutral centered position with respect to each other, said means including a resilient member contained in one of said elements and engageable by the other of said elements at least upon relative rotation of said elements.

2. A Walker according to claim 1 in which said stop means comprise grooves in one of said elements and pins extending from the other of said elements are received in said grooves.

3. A walker according to claim 2 in which said pins are movable between at least two positions and when in one position enable rotation in only one direction from center while blocking rotation in the other directon and when in another position enable rotation in said other direction while blocking rotation in said one direction.

4. A walker according to claim 1 in which said ground engaging cleat is upwardly arched to be higher in the center than at the front and rear and is open at both sides.

5. A walker according to claim -1 with the addition of a friction reducing bearing between said first and second elements, guides on said bearing in engagement with complemental guides on said elements.

6. A walker for use on an artificial support for a human leg comprising a first element formed as a base adapted to be anchored to said support, a second element formed as a ground engaging cleat, means mounting said second element in depending relationship to said first element and for limited rotation with self centering relationship with respect thereto, said means comprising a shaft extending between and secured to both of said elements and at least the connection between said shaft and at least one of said elements being formed from resilient material.

7. A walker according to claim 6 in which said ground engaging cleat is upwardly arched to be higher in the center than at the front and rear and is open at both sides.

8. A walker according to claim 6 with the addition of a friction reducing bearing bet-ween said first and second elements, guides on said bearing in engagement with complemental guides on said elements.

9. A walker for use on an artificial support for the human leg comprising a first element formed as a base adapted to be anchored to the support, a second element formed as a ground engaging cleat, means mounting said second element in depending relationship to said first element and for limited self centering rotational relationship with respect thereto, said means comprising a shaft formed from resilient material and secured to both of said elements and extending therebetween.

1 0. A walker according to preceding claim 9 in which one of said first and second elements and said shaft are formed as an integral unit from resilient material.

11. A walker according to claim 9 in which said ground engaging cleat is upwardly arched to be higher in the center than at the front and rear and is open at both sides.

12. A walker according to claim 10 in which said ground engaging cleat is upwardly arched to be higher in the center than at the front and rear and is open at both sides.

13. A walker according to claim 9 with the addition of a friction reducing bearing between said first and second elements and guides on said bearing in engagement with complemental guides on said elements.

14. A walker according to claim 10 with the addition of a friction reducing bearing between said first and sec: ond elements and guides on said bearing in engagement with complemental guides on said elements.

References Cited UNITED STATES PATENTS 1,290,095 1/1919 Cook.

1,387,988 8/ 1921 Kaplan.

2,888,919 6/1959 Unkauf 128-835 3,068,861 12/1962 Hoopes 12883.5 2,264,570 12/1941 Holden 12883.5 2,605,761 8/ 19512 Wiltrout 12883.5 3,307,536 3/1967 Blosser 12883.5

FOREIGN PATENTS 1,014,877 6/ 1952 France.

OTHER REFERENCES De Puy Orthopedic Appliances, splints and fracture equipment catalog, De Puy Mfg. Co., Inc., Warsaw, Ind., p. 131, published 1964.

RICHARD A. GAUDET, Primary Examiner R. L. FRINKS, Assistant Examiner US. Cl. X.R. 128-80; 36-39, 59 

